A satellite network system may provide high-speed Internet protocol (IP) satellite connectivity between corporate operations (hub) and multiple remote sites in a star topology. The hub demodulator subsystem (HDS) may be designed to support inroute processing at a high aggregate symbol rate, for example, of 9.8 Megasymbols per second (Msps), the aggregation comprising multiple high speed inroutes operating at various rates, for example, 2 Msps, 4 Msps and 6 Msps. However, with a fixed aperture length, system throughput will decrease with the use of higher symbol rate inroutes for a given fixed spectrum capacity, making the use of high speed inroutes inefficient when compared to multiple lower speed inroutes that can be used within the same spectrum capacity. The relative burst overhead will increase, and throughput decrease, with increase in the inroute symbol rate for a given spectrum capacity. As the burst overhead is fixed, throughput will decrease with decrease in allocated burst length.
The aperture, fixed in duration for example at 125 μs, is a significant component of the total burst-to-burst overhead in an offset quadrature phase-shift keying (OQPSK) system. At very high symbol rates such as 4 Msps and 6 Msps, the slot time is reduced such that the aperture occupies a greater number of slots in a frame compared to the number of slots occupied by the aperture when using a lower symbol rate frame. Thus for a given frame format, slot sizing, and spectrum capacity, the number of slots used for overhead in a burst allocation increases significantly at high symbol rates, thereby reducing the inroute efficiency compared to lower symbol rate inroutes.